* Revises legality checks to account for traveling between the three game islands (PLA/BDSP/SWSH)
* Adds conversion mechanisms between the three formats, as well as flexible conversion options to backfill missing data (thanks GameFreak/ILCA for opting for lossy conversion instead of updating the games).
* Adds API abstractions for HOME data storage format (EKH/PKH format 1, aka EH1/PH1).
* Revises some APIs for better usage:
- `PKM` now exposes a `Context` to indicate the isolation context for legality purposes.
- Some method signatures have changed to accept `Context` or `GameVersion` instead of a vague `int` for Generation.
- Evolution History is now tracked in the Legality parse for specific contexts, rather than only per generation.
Existing `get`/`set` logic is flawed in that it doesn't work on Big Endian operating systems, and it allocates heap objects when it doesn't need to.
`System.Buffers.Binary.BinaryPrimitives` in the `System.Memory` NuGet package provides both Little Endian and Big Endian methods to read and write data; all the `get`/`set` operations have been reworked to use this new API. This removes the need for PKHeX's manual `BigEndian` class, as all functions are already covered by the BinaryPrimitives API.
The `StringConverter` has now been rewritten to accept a Span to read from & write to, no longer requiring a temporary StringBuilder.
Other Fixes included:
- The Super Training UI for Gen6 has been reworked according to the latest block structure additions.
- Cloning a Stadium2 Save File now works correctly (opening from the Folder browser list).
- Checksum & Sanity properties removed from parent PKM class, and is now implemented via interface.
Big thanks to @SciresM @sora10pls @Lusamine @architdate @ReignOfComputer for testing and contributing code / test cases. Can't add co-authors from the PR menu :(
Builds will fail because azure pipelines not yet updated with net6.
